file association fixes macOS

main.py

@@ -28,7 +28,7 @@ from PySide6.QtWidgets import (
     QApplication, QWidget, QMessageBox, QVBoxLayout, QHBoxLayout, QTextEdit, QScrollArea, QComboBox, QGridLayout, QSplitter, QDialogButtonBox, QHeaderView,
     QPushButton, QMainWindow, QLabel, QLineEdit, QGroupBox, QDialog, QMenu, QSpinBox, QTableWidget, QTableWidgetItem
 )
-from PySide6.QtCore import Signal, Qt, QTimer
+from PySide6.QtCore import QEvent, Signal, Qt, QTimer
 from PySide6.QtGui import QAction, QFontMetrics, QKeySequence, QIcon
 from PySide6.QtSvgWidgets import QSvgWidget # needed to show svgs when app is not frozen
 
@@ -488,7 +488,26 @@ class GroupAssignmentDialog(QDialog):
         return mappings
 
 
+ 
+class CustomApplication(QApplication):
+    """
+    macOS delivers a file-open request (double-clicking a registered
+    file, or dropping one on the Dock icon — whether the app is already
+    running or being launched fresh) as an Apple Event, which Qt exposes
+    as QEvent.Type.FileOpen. Windows/Linux never send this; they pass
+    the path as a normal argv argument, which startup_args.initial_file
+    already handles. Without this override, double-clicking a project
+    file on macOS launches the app but it never learns which file to open.
+    """
+    file_open_requested = Signal(str)
+ 
+    def event(self, e: QEvent) -> bool:
+        if e.type() == QEvent.Type.FileOpen:
+            self.file_open_requested.emit(e.file())
+            return True
+        return super().event(e)
 
+    
 
 class MainApplication(QMainWindow):
     """
@@ -1334,7 +1353,6 @@ class MainApplication(QMainWindow):
     def apply_splitter_ratios(self):
         """Applies saved ratio positions to main_h_splitter and left_v_splitter."""
         if hasattr(self, 'main_h_splitter'):
-            print("Splitter actual width:", self.main_h_splitter.width())
             total_width = self.main_h_splitter.width()
             if total_width > 0:
                 left_w = int(total_width * self.main_h_ratio)
@@ -2648,11 +2666,12 @@ if __name__ == "__main__":
     
     # Only run GUI in the main process
     if current_process().name == 'MainProcess':
-        app = QApplication(sys.argv)
+        app = CustomApplication(sys.argv)
         finish_update_if_needed(PLATFORM_NAME, APP_NAME, cfg_path, startup_args.finish_update)
         icon_ext = "icns" if PLATFORM_NAME == "darwin" else "ico"
         app.setWindowIcon(QIcon(resource_path(f"icons/main.{icon_ext}"))) 
         window = MainApplication(file_to_open=startup_args.initial_file)
+        app.file_open_requested.connect(window.project_manager.load_project)
         window.setWindowIcon(QIcon(resource_path(f"icons/main.{icon_ext}")))
         window.show()
         sys.exit(app.exec())